Communication among electronic devices has become commonplace and often serves as the mechanism for communication between parties. Electronic devices can be used for communicating among parties that are members of a group or are a subset of members of a group. Difficulties can arise in that communications and identities of parties often can not be trusted. Lack of trust can be caused by concerns such as communications being overheard by unauthorized parties or diverted to unintended recipients, contents changed without the knowledge of the communicating parties or communications originating from a source other than the apparent source.
Various forms of overcoming such concerns have been cumbersome to implement, not offered true identification of parties and/or required extensive communication among group members. Existing approaches to communications include the use of a group key distributed to members of the group. Group key management has been used to provide the combined functionality of confidentiality and authenticity on a group-wide basis. Typically, the group key is used to encrypt and decrypt various messages, and the ability of members to correctly encrypt or decrypt has been used as proof of membership of the group. Previous methods of implementing peer-to-peer confidentiality and authenticity of communications among the group members have also included certificate revocation lists, tickets issued by a central authority as in Kerberos and other approaches that require substantial communication among group members or substantial communication with a centralized authority.
Substantial communication requirements in conventional solutions may require a more robust communications capability in order to accommodate the periods of high overhead, such as at periods of group membership changes or other events, such as updating certificate revocation lists.